Fan control system

ABSTRACT

A fan control system includes multiple fans and a control unit. The control unit has a controller and a storage device. The storage device stores therein a first fan activation data. According to the first fan activation data, the control unit sequentially controls multiple output pins to output multiple output signals. Each fan storage device stores therein a second fan activation data identical to the first fan activation data. According to the corresponding output signal, the fan controller compares with the second fan activation data to find out the second fan activation data matching the output signal, then the fan controller outputs a drive signal to control and activate the fan to operate.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates generally to a fan control system, andmore particularly to a fan control system, which can lower instantaneousactivation current.

2. Description of the Related Art

In general, according to application extent, computers can be mainlyclassified into personal computers, server workstations, andsupercomputers. The personal computer generally employs one or twoprocessors mainly in charge of daily administrational affair processingand providing relevant multimedia entertaining functions. With respectto some more complicated operations, for example, 3D computer drafting,work stations are widely used. In order to meet the requirements of theInternet, a server equipped with two to four processors is mostlyemployed in this field. In some special application situations, a serversystem with 8 to 16 processors can be alternatively used. With respectto the application field of some specific usages, such as nuclear bombsimulation, weather usage, genetic engineering, which necessitatesuper-high operation performances, a supercomputer composed of tens oreven several hundreds or several thousands of serially connectedprocessors (or sub-computer system) is often adopted.

With the advance of the semiconductor manufacturing process, currently,the chipset, such as central processing unit, has been developed frommicrometer order to nanometer order. The number of the transistorscontained in the chipset is up to one hundred millions. Therefore, inoperation, the chipset will generate extremely high heat. In case theheat is not properly dissipated, the heat will accumulate in the casebody to lead to an overly high environmental system temperature. As aresult, the stability of the system will be deteriorated or even thesystem will malfunction or crash.

In the conventional technique, multiple cooling fans are installed inthe case body to provide convection so as to dissipate the heat. Thiscan effectively lower the temperature in the case body at a lowmanufacturing cost. Therefore, the cooling fans are widely used.However, such a conventional technique has a shortcoming in that theactivation initial times of the multiple fans are set as fixed.Therefore, when powering on the server, all the hardware equipmentdisposed in the server start to operate at full speed. Accordingly, allthe cooling fans installed in the server are activated to operate at thesame time. As shown in FIG. 1, such a circumstance is apt to result in asituation that, when the multiple fans are activated, the peak valuecurrent (or so-called current peak value) of the corresponding currentsignals 301, 302, 303, 304 are added together in accordance with thenumber of the fans. In this case, the summed current signal 300 of themultiple fans is a summed peak value current vertically upwardlysuperimposed. However, the system will limit the activation current ofthe fans and provide an over-current protection system. Therefore, whenthe multiple fans are activated, the summed peak value current 300 ofthe instantaneously superimposed current signals is too high, (that is,when the multiple fans are activated at the same time, the sum of thecorresponding currents is too high). This leads to greater consumptionof the power by the server. As a result, the system is apt to operateunstably or even malfunction or crash. Also, the system may mis-triggerthe over-current protection so that the multiple fans cannotsuccessfully activate and operate. In this case, the system willoverheat and shut down.

The applicant therefore provides a fan control system, which can lowerthe instantaneous activation current of the server when started so as tosolve the problems existing in the conventional technique.

SUMMARY OF THE INVENTION

It is therefore a primary object of the present invention to provide afan control system, which can lower instantaneous activation current.

It is a further object of the present invention to provide the above fancontrol system, which can achieve different lowered peak value currents.

To achieve the above and other objects, the fan control system of thepresent invention includes multiple fans and a control unit. The controlunit has a controller and a storage device connected with thecontroller. The controller has multiple output pins. The storage devicestores therein a first fan activation data. The first fan activationdata includes multiple different first activation time points andmultiple different first activation input values. Each first activationtime point corresponds to each first activation input value. Accordingto the multiple first activation time points, the controllersequentially controls the multiple output pins to output multiple outputsignals corresponding to the multiple first activation input values. Themultiple output pins are connected with the multiple corresponding fans.Each fan is provided with a fan controller and a fan storage deviceconnected with the fan controller. The fan storage device stores thereina second fan activation data identical to the first fan activation data.The second fan activation data includes multiple different secondactivation time points and multiple different second activation inputvalues. Each second activation time point corresponds to each secondactivation input value. According to the corresponding output signals,the fan controller compares with the second fan activation data in thefan storage device to find out the second fan activation data matchingthe output signal, whereby at each second activation time point of thesecond fan activation data, the fan controller outputs a drive signalcorresponding to each second activation input value to control andactivate the fan to operate. By means of the design of the fan controlsystem of the present invention, the instantaneously superimposedactivation current of the multiple fans is effectively lowered so thatthe entire fan control system can stably operate.

BRIEF DESCRIPTION OF THE DRAWINGS

The structure and the technical means adopted by the present inventionto achieve the above and other objects can be best understood byreferring to the following detailed description of the preferredembodiments and the accompanying drawings, wherein:

FIG. 1 is a schematic diagram showing the waveform of the activationpeak value current of multiple conventional fans;

FIG. 2 is a block diagram of a preferred embodiment of the presentinvention;

FIG. 3A is the first fan activation data table of a preferred embodimentof the present invention;

FIG. 3B is the second fan activation data tables of the first and secondfans of a preferred embodiment of the present invention;

FIG. 3C is the second fan activation data tables of the third and fourthfans of a preferred embodiment of the present invention;

FIG. 4 is a schematic diagram showing the waveform of the power signalsand summed power signal of multiple fans of a preferred embodiment ofthe present invention;

FIG. 5A is the fan activation data table of a modified embodiment of thepresent invention; and

FIG. 5B is the fan activation data table of another modified embodimentof the present invention; and

FIG. 6 is the fan activation data table of another modified embodimentof the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Please refer to FIGS. 2 to 5B. FIG. 2 is a block diagram of a preferredembodiment of the present invention. FIG. 3A is the first fan activationdata table of a preferred embodiment of the present invention. FIG. 3Bis the second fan activation data tables of the first and second fans ofa preferred embodiment of the present invention. FIG. 3C is the secondfan activation data tables of the third and fourth fans of a preferredembodiment of the present invention. FIG. 4 is a schematic diagramshowing the waveform of the power signals and summed power signal ofmultiple fans of a preferred embodiment of the present invention. FIG.5A is the fan activation data table of a modified embodiment of thepresent invention. FIG. 5B is the fan activation data table of anothermodified embodiment of the present invention. The fan control system 1of the present invention is applied to an electronic apparatus (such asa computer, a server, a communication chassis or other electronicapparatus). The fan control system 1 includes multiple fans and acontrol unit 15. In this embodiment, the multiple fans are selectively afirst fan 10, a second fan 11, a third fan 12 and a fourth fan 13 forillustration purposes. The control unit 15 has a controller 150 and astorage device 157. In this embodiment, the controller 150 is, but notlimited to, a microcontroller unit (MCU). The controller 150 hasmultiple output pins and a power pin 156 for receiving an input voltageVc (such as 12 volts or 10 volts). The output pins are respectivelyelectrically connected with the corresponding fans.

The multiple output pins are a first output pin 151, a second output pin152, a third output pin 153 and a fourth output pin 154. In thisembodiment, the first, second, third and fourth output pins 151, 152,153, 154 are pulse width modulation (PWM) output pins for outputting PWMsignals, (that is, the output signals). That is, the first, second,third and fourth output pins 151, 152, 153, 154 serve to sequentiallyoutput a first output signal S1, a second output signal S2, a thirdoutput signal S3 and a fourth output signal S4, which are transmitted tothe corresponding first, second, third and fourth fans 10, 11, 12, 13.The first, second, third and fourth output pins 151, 152, 153, 154 arecorrespondingly electrically connected with the first, second, third andfourth fans 10, 11, 12, 13. In practice, in addition to the first,second, third and fourth output pins 151, 152, 153, 154, the controller150 further includes other pins for executing other controls.

In a preferred embodiment, the controller 150 can be a processor or adigital signal processor. The output pins are voltage output pins orstring data output pins or other specific pins (such as I/O pins) foroutputting the output signals (such as voltage signals or string datasignals) to control and activate the corresponding fans.

Moreover, in the present invention, the number of the multiple outputpins and the number of the fans are not limited to four. According tothe heat dissipation requirement of the system, a user can previouslydesign and selectively adjustably employ a controller 150 with more thantwo output pins in cooperation with more than two fans. For example, thecontroller 150 can have five output pins (such as five PWM output pins)electrically connected with five corresponding fans. The five outputpins serve to output and transmit the five output signals to the fivecorresponding fans.

The storage device 157 can be a random access memory, a flash RAM, ahard disk drive (HDD), a solid state disk (SSD) or a USB flash drive orany other data access unit. The storage device 157 is electricallyconnected with the controller 150. The storage device 157 stores thereina first fan activation data 17. In this embodiment, the first fanactivation data 17 are such as the fan activation data table (as shownin FIG. 3A). The first fan activation data 17 include multiple differentfirst activation time points, multiple different first activation inputvalues and an input voltage value 178. The input voltage value 178 isthe input voltage value 178 (such as 12 volts or 10 volts) in the firstfan activation data 17 corresponding to each fan, (that is, the first,second, third and fourth fans 10, 11, 12, 13). The multiple firstactivation time points are five first activation time points, (that is,first, second, third, fourth and fifth first activation time points 171a, 172 a, 173 a, 174 a, 175 a) corresponding to each fan. The five firstactivation time points are different from each other. The multiple firstactivation input values are five first activation input values, (thatis, first, second, third, fourth and fifth first activation input values171 b, 172 b, 173 b, 174 b, 175 b) corresponding to each fan. The fivefirst activation input values are different from each other. Inaddition, the five first activation time points correspond to the fivefirst activation input values. In this embodiment, there are four setsof five first activation time points and five first activation inputvalues in the first fan activation data 17 corresponding to the fourfans 10, 11, 12, 13 for illustration purposes.

The five first activation time points of each set are later than eachother by a certain time. For example, the fifth first activation timepoint 175 a of each set is later than the fourth first activation timepoint 174 a. The fourth first activation time point 174 a is later thanthe third first activation time point 173 a. The third first activationtime point 173 a is later than the second first activation time point172 a. The second first activation time point 172 a is later than thefirst first activation time point 171 a. In addition, the first set offive first activation time points are later than the correspondingsecond, third and fourth sets of first activation time points. Forexample, as shown in FIG. 3A, the first first activation time point 171a of the first set corresponding to the first fan 10 is earlier than thefirst first activation time point 171 a of the second set (or the thirdset or fourth set) corresponding to the second fan 11 (or the third fan12 or the fourth fan 13). The second second activation time point 172 aof the first set corresponding to the first fan 10 is earlier than thesecond second activation time point 172 a of the second set (or thethird set or fourth set) corresponding to the second fan 11 (or thethird fan 12 or the fourth fan 13), and so on as shown in FIG. 3A. Inaddition, the fifth first activation input value 175 b of each set islarger than the fourth first activation input value 174 b. The fourthfirst activation input value 174 b is larger than the third firstactivation input value 173 b. The third first activation input value 173b is larger than the second first activation input value 172 b. Thesecond first activation input value 172 b of each set is larger than thefirst first activation input value 171 b.

In addition, according to the multiple first activation time points, thecontroller 150 sequentially controls the multiple output pins to outputthe multiple output signals corresponding to the multiple firstactivation input values. That is, according to the input voltage Vc, thecontroller 150 compares with the first fan activation data 17 in thestorage device 157 to find out the input voltage value 178 (such as 12volts) matching the input voltage Vc (such as 12 volts). Therefore,according to the five first activation time points compared and foundout from the first fan activation data 17 corresponding to the first,second, third and fourth fans 10, 11, 12, 13, the controller 150sequentially controls the first, second, third and fourth output pins151, 152, 153, 154 to output and transmit the first, second, third andfourth output signals S1, S2, S3, S4 corresponding to the five firstactivation input values of the first, second, third and fourth fans 10,11, 12, 13 to the corresponding first, second, third and fourth fans 10,11, 12, 13.

Please refer to FIG. 5A. In a preferred embodiment, the storage device157 stores therein multiple first fan activation data 17. In each of thefirst fan activation data 17, the input voltage values 178 (such as 12volts or 10 volts) are different. For example, the input voltage values178 in the first first fan activation data 17 is such as 12 voltscorresponding to the fan of 12 volts. The input voltage values 178 inthe second second fan activation data 17 is such as 10 voltscorresponding to the fan of 10 volts. As shown in FIG. 5B, in a modifiedembodiment, the storage device 157 stores therein multiple first fanactivation data 17. In each of the first fan activation data 17, thedata (including the input voltage value, the first activation inputvalues and the first activation time points) have different types,wherein the data type of a first fan activation data 17 is PWM withdifferent duty ratio, (that is, different activation input value)corresponding to different activation time point to operate. The datatype of a second fan activation data 17 is different voltage, (that is,different activation input value) corresponding to different activationtime point to operate. The data type of a third fan activation data 17is different character string data (such as different digital characterstring, that is, different activation input value) corresponding todifferent activation time point to operate.

Please refer to FIGS. 2, 3A, 3B and 3C. Each fan, (that is, the first,second, third and fourth fans 10, 11, 12, 13) is provided with a fancontroller 101, 111, 121, 131 and a fan storage device 102, 112, 122,132 connected with the fan controller 101, 111, 121, 131. The fanstorage device 102, 112, 122, 132 stores therein a second fan activationdata 18 identical to the first fan activation data 17. The second fanactivation data 18 include multiple different second activation timepoints, multiple different second activation input values and a fanvoltage value 186 identical to the corresponding input voltage value.Each second activation time point corresponds to each second activationinput value. The multiple second activation time points are five secondactivation time points 181 a, 182 a, 183 a, 184 a, 185 a) different fromeach other. The multiple second activation input values are five secondactivation input values 181 b, 182 b, 183 b, 184 b, 185 b) differentfrom each other. In addition, the five second activation time pointscorrespond to the five second activation input values. The first,second, third and fourth fans correspond to the five second activationtime points 181 a, 182 a, 183 a, 184 a, 185 a and the five secondactivation input values 181 b, 182 b, 183 b, 184 b, 185 b in the fanstorage devices 102, 112, 122, 132.

Moreover, the data (including the first activation input value, thefirst activation time point and the input voltage value) of each firstfan activation data 17 in the controller 150 are in adaptation to andmatch the corresponding data (including the second activation inputvalue, the second activation time point and the fan voltage value) ofthe second fan activation data 18 in each fan. In addition, in thisembodiment, the five second activation time points, (that is, the firstto the fifth second activation time points 181 a, 182 a, 183 a, 184 a,185 a) and the five second activation input values, (that is, the firstto the fifth second activation input values 181 b, 182 b, 183 b, 184 b,185 b) of the first fan 10 (the second fan 11, the third fan 12 or thefourth fan 13) are identical to the five first activation time points171 a, 172 a, 173 a, 174 a, 175 a and the five first activation inputvalues 171 b, 172 b, 173 b, 174 b, 175 b of the corresponding first set(the second set, the third set or the fourth set) and thus will not beredundantly described hereinafter. Also, the fan voltage value 186 isthe voltage value in the second fan activation data 18 corresponding tothe fan. Moreover, in this embodiment, the voltage values of the first,second, third and fourth fans 10, 11, 12, 13 are identical to eachother.

According to the corresponding output signal, the fan controllers 101,111, 121, 131 compare with the second fan activation data 18 in the fanstorage devices 102, 112, 122, 132 to find out the second fan activationdata 18 matching the output signal. At each second activation time pointof the second fan activation data 18, a drive signal corresponding toeach second input value is output to control and activate the fan tooperate. That is, according to the first output signal S1 (or the secondoutput signal S2 or the third output signal S3 or the fourth outputsignal S4), the fan controller 101 (or 111 or 121 or 131) of the firstfan 10 (or the second fan 11 or the third fan 12 or the fourth fan 13)compares with the second fan activation data 18 in the fan storagedevice 102 (or 112 or 122 or 132) to find out the second fan activationdata 18 matching the first output signal S1 (or the second output signalS2 or the third output signal S3 or the fourth output signal S4).Accordingly, at each second activation time point of the second fanactivation data 18, a first drive signal (or a second drive signal or athird drive signal or a fourth drive signal) corresponding to eachsecond input value is output by the fan controller 101 (or 111 or 121 or131) of the first fan 10 (or the second fan 11 or the third fan 12 orthe fourth fan 13) to control and activate the first fan 10 (or thesecond fan 11 or the third fan 12 or the fourth fan 13) to operate andobtain the power signals (such as the first, second, third and fourthcurrent signals 103, 113, 123, 133) respectively corresponding to thefirst, second, third and fourth fans 10, 11, 12, 13 and the summed powersignal 100 of all the fans as shown in FIG. 4. Also, the peak valuecurrents (or so-called current peak values) of the first, second, thirdand fourth current signals 103, 113, 123, 133 are staggered. Forexample, according to the first output signal S1 such as a PWM signalwith 25% duty ratio, the fan controller 101 of the first fan 10 compareswith the second fan activation data 18 in the fan storage device 102 tofind out the second activation input value 182 b with such as 25% dutyratio of the second fan activation data 18 matching the first outputsignal S1. Accordingly, at the second activation time point 182 a suchas 0.7 second of the second fan activation data 18, the fan controller101 of the first fan 10 outputs the first drive signal such as a PWMsignal with 25% duty ratio corresponding to the second activation inputvalue 182 b with such as 25% duty ratio to control and activate thefirst fan 10 to operate, and so on with respect to the second, third andfourth fans 11, 12, 13. Therefore, in the present invention, the first,second, third and fourth fans 10, 11, 12, 13 are activated at differenttimes, whereby the first, second, third and fourth fans 10, 11, 12, 13themselves can judge the activation time to operate. Accordingly, thepeak values of the first, second, third and fourth drive signals S1, S2,S3, S4 are staggered so as to achieve the effect that the first, second,third and fourth fans 10, 11, 12, 13 are activated at different timesand the instantaneous activation current is lowered.

In addition, by means of the fan control system 1 of the presentinvention, a user can preset the data of the first and second fanactivation data 17, 18, such as the first and second activation inputvalues, the first and second activation time points, the input voltagevalue 178 and the fan voltage value 186) so as to set up differentoutput signals, (that is, the first, second, third and fourth outputsignals S1, S2, S3, S4) and different drive signals to define theinitial activation time points of the multiple fans, (that is, thefirst, second, third and fourth fans 10, 11, 12, 13) after powered.Accordingly, the multiple fans themselves can judge and activate (oroperate) according to the corresponding time difference. Therefore, whenactivated, the summed power signal 100 of all the fans is a summed peakvalue current in the form of an elongated stair obliquely extending fromlower side to upper side (as shown in FIG. 4). Accordingly, the first,second, third and fourth fans 10, 11, 12, 13 are activated at differenttimes and the superimposed peak value current of the multiple activatedfans can be effectively lowered. In addition, the entire fan controlsystem 1 can effectively stably operate to avoid mis-triggering of theover-current protection of the fan control system 1.

An embodiment of the present invention is taken as an example forillustration as follows:

When the fan control system 1 is powered on, the controller 150 receivesthe input voltage Vc such as 12 volts and compares with the first fanactivation data 17 in the storage device 157 to find out the inputvoltage value 178 such as 12 volts matching the input voltage Vc.Thereafter, the controller 150 reads the five first activation timepoints 171 a, 172 a, 173 a, 174 a, 175 a and the five first activationinput values 171 b, 172 b, 173 b, 174 b, 175 b corresponding to thefirst, second, third and fourth fans 10, 11, 12, 13 in the first fanactivation data 17 corresponding to the input voltage value 178. At thesame time, according to the four sets of the five first activation timepoints 171 a, 172 a, 173 a, 174 a, 175 a, the controller 150sequentially at the first, second, third and fourth sets of the fivefirst activation time points 171 a, 172 a, 173 a, 174 a, 175 a controlsthe first, second, third and fourth output pins 151, 152, 153, 154 tooutput the first, second, third and fourth output signals S1, S2, S3, S4corresponding to the four sets of the five first activation input values171 b, 172 b, 173 b, 174 b, 175 b. The first fan 10 first receives thefirst output signal S1 such as a PWM signal with 25% duty ratio. The fancontroller 101 of the first fan 10 compares with the second fanactivation data 18 in the fan storage device 102 to find out the secondactivation input value 182 b with such as 25% duty ratio of the secondfan activation data 18 matching the first output signal S1. At thistime, at the second activation time point 182 a such as 0.7 second, thefan controller 101 of the first fan 10 outputs the first drive signal(such as a PWM signal with 25% duty ratio) corresponding to the secondactivation input value 182 b with such as 25% duty ratio to control andactivate the first fan 10 to operate. Then, at the second activationtime point 182 a later than the first fan 10 by such as 0.2 second,(that is, waiting for 0.9 second), the fan controller 111 of the secondfan 11 outputs the second drive signal (such as a PWM signal with 25%duty ratio) to control and activate the second fan 11 to operate. Then,at the second second activation time point 181 a later than the secondfan 10 by such as 0.2 second, (that is, waiting for 1.1 second), the fancontroller 121 of the third fan 12 outputs the third drive signal (suchas a PWM signal with 25% duty ratio) to control and activate the thirdfan 11 to operate. Finally, at the second activation time point 181 alater than the third fan 12 by such as 0.2 second, (that is, waiting for1.3 second), the fan controller 131 of the fourth fan 13 outputs thefourth drive signal (such as a PWM signal with 25% duty ratio) tocontrol and activate the fourth fan 13 to operate. At the other foursecond activation time points 181 a, 183 a, 184 a, 185 a of the first,second, third and fourth fans 10, 11, 12, 13, the first, second, thirdand fourth drive signals corresponding to the other four secondactivation input values 181 b, 183 b, 184 b, 185 b are output to controland activate the fan to operate in a similar manner.

As shown in FIGS. 2 and 6. In a modified embodiment, the five firstactivation time points and the five first activation input values 1 inthe single first fan activation data 17 in the controller 150 correspondto multiple fans (such as the first, second, third and fourth fans 10,11, 12, 13). In addition, the second activation data 18 in the multiplefans are identical to the first fan activation data 17 in the controller150. A user can preset the sequence in which the multiple output pinsoutput the multiple output signals and preset the activation inputvalues corresponding to each output pin when the controller 150 isinitially powered on. For example, when the fan control system 1 ispowered on, the controller 150 controls the first, second, third andfourth output pins 151, 152, 153, 154 to sequentially output the first,second, third and fourth output signals S1, S2, S3, S4 at an interval(such as one second) corresponding to the first preset activation inputvalue as 0% duty ratio, the second preset activation input value 172 bas 25% duty ratio, the third preset activation input value as 50% dutyratio and the four preset activation input value as 75% duty ratio andsequentially transmit the first, second, third and fourth output signalsS1, S2, S3, S4 to the corresponding first, second, third and fourth fans10, 11, 12, 13. The first fan 10 first receives the corresponding firstoutput signal S1 such as a PWM signal with 25% duty ratio. The fancontroller 101 compares with the second fan activation data 18 to findout the first second activation input value 181 b with such as 0% dutyratio of the second fan activation data 18 matching the first outputsignal S1. At this time, the fan controller 101 outputs the first drivesignal (such as a PWM signal with 0% duty ratio) corresponding to thefirst output signal S1 to control and activate the first fan 11 toinitially operate (activated to be operated). Then, the fan controller111 of the second fan 11 outputs the second drive signal (such as a PWMsignal with 25% duty ratio) corresponding to the second secondactivation input value 182 b as 25% duty ratio to control and activatethe second fan 11 to initially operate. Then, the fan controller 121 ofthe third fan 12 outputs the third drive signal (such as a PWM signalwith 50% duty ratio) corresponding to the third second activation inputvalue 183 b as 50% duty ratio to control and activate the third fan 12to initially operate. Finally, the fan controller 131 of the fourth fan13 outputs the fourth drive signal (such as a PWM signal with 75% dutyratio) corresponding to the fourth second activation input value 184 bas 75% duty ratio to control and activate the fourth fan 13 to initiallyoperate. At this time, after all the multiple fans have been initiallyoperated, according to the first fan activation data 17 in cooperationwith the second fan activation data 18 of the multiple fans, thecontroller 150 controls to the multiple fans to sequentially operate.

Therefore, by means of the design of the fan control system 1 of thepresent invention, the activation time points of all the fans aredelayed and staggered, whereby the fan control system 1 can effectivelylower the instantaneously superimposed activation current of themultiple fans. Also, the system is prevented from being turned on/offwhen not completely initially powered on. In addition, the fan controlsystem 1 can effectively avoid mis-triggering of the over-currentprotection so that the fan control system 1 can stably operate.

The present invention has been described with the above embodimentsthereof and it is understood that many changes and modifications in suchas the form or layout pattern or practicing step of the aboveembodiments can be carried out without departing from the scope and thespirit of the invention that is intended to be limited only by theappended claims.

What is claimed is:
 1. A fan control system comprising: a control unithaving a controller and a storage device connected with the controller,the controller having multiple output pins, the storage device storingtherein a first fan activation data, the first fan activation dataincluding multiple different first activation time points and multipledifferent first activation input values, each first activation timepoint corresponding to each first activation input value, according tothe multiple first activation time points, the controller sequentiallycontrolling the multiple output pins to output multiple output signalscorresponding to the multiple first activation input values; andmultiple fans connected with the multiple corresponding output pins,each fan being provided with a fan controller and a fan storage deviceconnected with the fan controller, the fan storage device storingtherein a second fan activation data identical to the first fanactivation data, the second fan activation data including multipledifferent second activation time points and multiple different secondactivation input values, each second activation time point correspondingto each second activation input value, according to the correspondingoutput signals, the fan controller comparing with the second fanactivation data in the fan storage device to find out the second fanactivation data matching the output signal, whereby at each secondactivation time point of the second fan activation data, the fancontroller outputs a drive signal corresponding to each secondactivation input value to control and activate the fan to operate. 2.The fan control system as claimed in claim 1, wherein the multiple firstactivation time points are five first activation time pointscorresponding to each fan, the five first activation time points beingdifferent from each other, the multiple first activation input valuesbeing five first activation input values corresponding to each fan, thefive first activation input values being different from each other, thefive first activation time points corresponding to the five firstactivation input values.
 3. The fan control system as claimed in claim2, wherein the multiple second activation time points are five secondactivation time points, the five second activation time points beingdifferent from each other, the multiple second activation input valuesbeing five second activation input values, the five second activationinput values being different from each other, the five second activationtime points corresponding to the five second activation input values. 4.The fan control system as claimed in claim 3, wherein the multiple fanare a first fan, a second fan, a third fan and a fourth fan, the first,second, third and fourth fans corresponding to the five secondactivation time points and the five second activation input values ofthe fan storage devices, the multiple output pins being a first outputpin, a second output pin, a third output pin and a fourth output pin,the first, second, third and fourth output pins being electricallyconnected with the corresponding first, second, third and fourth fans,the first, second, third and fourth output pins serving to sequentiallyoutput a first output signal, a second output signal, a third outputsignal and a fourth output signal, which are transmitted to thecorresponding first, second, third and fourth fans.
 5. The fan controlsystem as claimed in claim 4, wherein according to the five firstactivation time points corresponding to the first, second, third andfourth fans, the controller sequentially controls the first, second,third and fourth output pins to output the first, second, third andfourth output signals corresponding to the five first activation inputvalues of the first, second, third and fourth fans to the first, second,third and fourth fans.
 6. The fan control system as claimed in claim 4,wherein according to the first output signal, the fan controller of thefirst fan compares with the second fan activation data in the fanstorage device to find out the second fan activation data matching thefirst output signal, whereby at each second activation time point of thesecond fan activation data, the fan controller of the first fan outputsa first drive signal corresponding to each second activation input valueto control and activate the first fan to operate, according to thesecond output signal, the fan controller of the second fan comparingwith the second fan activation data in the fan storage device to findout the second fan activation data matching the second output signal,whereby at each second activation time point of the second fanactivation data, the fan controller of the second fan outputs a seconddrive signal corresponding to each second activation input value tocontrol and activate the second fan to operate.
 7. The fan controlsystem as claimed in claim 4, wherein according to the third outputsignal, the fan controller of the third fan compares with the second fanactivation data in the fan storage device to find out the second fanactivation data matching the third output signal, whereby at each secondactivation time point of the second fan activation data, the fancontroller of the third fan outputs a third drive signal correspondingto each second activation input value to control and activate the thirdfan to operate, according to the fourth output signal, the fancontroller of the fourth fan comparing with the second fan activationdata in the fan storage device to find out the second fan activationdata matching the fourth output signal, whereby at each secondactivation time point of the second fan activation data, the fancontroller of the fourth fan outputs a fourth drive signal correspondingto each second activation input value to control and activate the fourthfan to operate.
 8. The fan control system as claimed in claim 4, whereinaccording to an input voltage, the controller compares with the firstfan activation data in the storage device to find out an input voltagevalue matching the input voltage, whereby according to the five firstactivation time points compared and found out from the first fanactivation data corresponding to the first, second, third and fourthfans, the controller sequentially controls the first, second, third andfourth output pins to output and transmit the first, second, third andfourth output signals corresponding to the five first activation inputvalues of the first, second, third and fourth fans to the correspondingfirst, second, third and fourth fans.
 9. The fan control system asclaimed in claim 1, wherein the multiple output pins are pulse widthmodulation (PWM) output pins, voltage output pins or string data outputpins.
 10. The fan control system as claimed in claim 1, wherein themultiple output signals are pulse width modulation (PWM) signals,voltage signals or string data signals.
 11. The fan control system asclaimed in claim 1, wherein the controller is a microcontroller unit, aprocessor or a digital signal processor.
 12. The fan control system asclaimed in claim 1, wherein the storage device is a random accessmemory, a flash RAM, a hard disk drive (HDD), a solid state disk (SSD)or a USB flash drive.